The present invention provides the surprising discovery that feeding a composition comprising a combination of a modified yeast cell wall extract and a clay such as a zeolite, bentonite, or other aluminosilicate clay has an additive binding effect for reducing effects of fungal alkaloid diseases such as fescue toxicosis. In particular, the invention provides a method and composition for reducing unhealthful effects of ergot alkaloids, especially ergopeptine and clavine alkaloids, present in forages such as fescue hay infected with fungi such as Neotyphodium coenophialum (formerly Acremonium coenophialum).
The compositions of the invention are comprised of a modified yeast cell wall extract and aluminosilicate clay. In a preferred embodiment, the composition contains between about 1% and about 10% aluminum silicate clay, and about 90% to 99% modified yeast cell wall extract. Especially preferred compositions of the invention comprise from between about 2% to about 4% aluminum silicate and between about 96% and about 98% modified yeast cell wall extract.
In one embodiment, the modified yeast cell wall extract is available from Alltech, Inc., Nicholasville, Ky. and the aluminum silicate is a standard commercial grade available from a variety of sources. The yeast cell wall extract is extracted from a yeast organism, which can be any of a number of yeasts. Preferred embodiments of the invention, however, utilize cell wall extracts from Saccharomyces species, e.g. S. cerevisiae, or from a Torula yeast.
The compositions described may be fed to any grazing animal, including but not limited to ruminant and equine species. When admixed with feed or fed as a supplement, the compositions with their increased alkaloid binding capability decrease absorption or uptake of the alkaloids by the affected animal, improving performance and health and reducing incidence of endophyte-related diseases such as fescue toxicosis or ryegrass staggers. The composition comprises feeding a combination of a modified yeast cell wall extract and a clay such as a zeolite, bentonite, or other aluminosilicate clay. This combination has a surprising and unexpected additive binding effect for reducing effects of alkaloid contamination on animals consuming infected feedstuffs.
Tall fescue (F. arundinacea) is the major forage grass in the eastern and northwestern United States, covering 10,140,000 hectares in 21 states. It is the most abundant and economically important cool season perennial grass grown in the U.S. Tall fescue is desirable because of its ease of establishment, range of adaptation, and extended grazing season. The nutritional composition compares favorably with other cool season grasses, however, performance of cattle grazing fescue during summer months is generally less than would be expected for the nutrient composition of the grass.
As tall fescue became a popular forage grass in the mid-twentieth century, reports of adverse effects on cattle grazing fescue began to accumulate. It was not until 1977 that conclusive evidence of the presence of the endophytic fungus A. coenophialum in tall fescue and its correlation to fescue toxicosis in cattle was reported. The presence of endophyte was reported in 58% of forage samples submitted from 26 states. A more recent study of 200 fields reported endophyte infection (EI) rates as high as 97%, and infection levels of individual fields greater than 67% for the majority of the fields. The problem is not localized in the US, as EI tall fescue has been reported in New Zealand, Italy, Wales, France and Poland.
Economic losses due to endophyte infections of tall fescue are substantial. Cattle grazing EI tall fescue have been shown to have reduced weaning weights and reduced conception rates. Losses to the equine industry can be substantial due to reduced reproductive performance in mares and losses to the dairy industry are mainly due to reduced milk production. Wildlife is also affected by EI tall fescue, because of the negative impact on hunting and hunting permit sales.
A variety of different symptoms including reduced body weight gain, increased body temperature, rough hair coat, reduced reproductive performance, fescue foot, excessive salivation, lower milk production and lower serum prolactin levels have been reported in animals consuming EI tall fescue. Research has been conducted on horses, sheep, cattle, quail, rabbits, and rats. It is pertinent to briefly discuss the effects on cattle and horses.
The earliest symptom recognized in cattle grazing EI tall fescue is fescue foot, a condition in which foot tissue death occurs in animals grazing on endophyte infested fescue pastures. Ergot alkaloids have been found to have a vasoconstrictive effect in vitro, decreasing blood flow to extremities, explaining the development of fescue foot. The vasoconstriction reduces blood flow to the skin affecting thermoregulation. Increased rectal temperatures have also been reported in animals fed EI tall fescue.
The two most significant losses caused by fescue toxicosis are reductions in feed intake and body weight gain. Reduction in weight gain have been noticed in cattle and to a lesser extent in horses. It has been suggested that reduced feed intake may be due to physical and physiological mechanisms of the toxins. The increased body temperature might be one of the main factors involved in depressing intake. Reduced feed intake in combination with a reduction in digestibility is the reason for weight gain depression.
Major reproductive problems in cattle and horses have been related to EI tall fescue. Fescue toxins affect reproduction in both males and females. The majority of research in this area has been done with females, focusing mainly on pregnant mares. Agalactia is the most commonly reported clinical sign in mares consuming infected fescue. Other effects in mares include prolonged gestation, thickened placentas, extremely high levels of foal mortality, and dystocia. The mechanisms thought to be responsible for reproductive problems are, decreased concentrations of prolactin and melatonin, vasoconstriction affecting blood flow to internal organs, and hyperthermia. Accordingly, methods and compositions capable of reducing effects of plant alkaloids causing diseases such as fescue toxicity and ryegrass staggers would be of great value.
Accordingly, it is a primary object of the present invention to provide a method for binding and subsequent inactivation of alkaloids associated with diseases such as fescue toxicity.
It is a further object of the present invention to provide a method for binding and subsequent inactivation of alkaloids associated with diseases such as fescue toxicity comprising a combination of a modified yeast cell wall extract and a mineral clay such as a zeolite or bentonite clay, or aluminum silicate.
Yet another object of the present invention is to provide a composition comprising a combination of a modified yeast cell wall extract and a mineral clay as described above which provides a surprising and unexpected additive binding effect for inactivation of alkaloids associated with diseases such as fescue toxicity,
Additional objects, advantages and other novel features of the invention will be set forth in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned with the practice of the invention. To achieve the foregoing and other objects, and in accordance with the purposes of the present invention as described herein, a novel method is described for binding and inactivation of alkaloids associated with diseases such as fescue toxicity. In particular, the invention provides a method and a composition for inactivation of alkaloids associated with diseases such as fescue toxicity encompassing a modified yeast cell wall extract and aluminosilicate. The yeast cell wall is extracted from a yeast organism which can be any of a number of yeasts. The aluminosilicate is a standard commercial grade available from a variety of sources.
The compositions provided by the invention can be fed to any animal including, but not limited to, bovine, equine, ovine, and caprine species. When admixed with feed or fed as a supplement, the compositions with their surprisingly increased alkaloid-binding capacity decrease absorption or uptake of the alkaloids by the affected animal, thereby improving performance and health, and reducing the incidence of alkaloid associated diseases such as fescue toxicity.